Conventionally, in various technical fields such as the field of electronic devices, application of a composition containing a polymer to a member has been conducted.
For example, a method of producing a composite in which a composition containing a polymer such as polyethyleneimine or a polyethyleneimine derivative having cationic functional groups and having a weight average molecular weight of from 2,000 to 1,000,000 and having a pH of from 2.0 to 11.0 is applied to the surfaces of members A and B having predetermined conditions is known (see, for example, Patent Document 1). Patent Document 1 describes that a composite member to which a composition is applied is washed with a rinsing liquid containing a polyvalent carboxylic acid.    Patent Document 1 WO 2014/156616